ClasspathScanner.java

/*
 * Copyright 2008 Whohoo Licensed under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the
 * License. You may obtain a copy of the License at
 * http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable
 * law or agreed to in writing, software distributed under the License is
 * distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the specific
 * language governing permissions and limitations under the License.
 */

package com.googlecode.mycontainer.util.cpscanner;

import java.net.URL;
import java.security.CodeSource;
import java.security.ProtectionDomain;
import java.util.ArrayList;
import java.util.List;

import com.googlecode.mycontainer.util.cpscanner.plugin.DirectoryClasspathPlugin;
import com.googlecode.mycontainer.util.cpscanner.plugin.ZipClasspathPlugin;

public class ClasspathScanner implements ScannerPlugin {

	private final List<ScannerPlugin> plugins = new ArrayList<ScannerPlugin>();

	private final List<ScannerListener> listeners = new ArrayList<ScannerListener>();

	public ClasspathScanner() {
		plugins.add(new ZipClasspathPlugin());
		plugins.add(new DirectoryClasspathPlugin());
	}

	public void addListener(ScannerListener listener) {
		this.listeners.add(listener);
	}

	public void scan(Class<?> clazz) {
		ProtectionDomain pd = clazz.getProtectionDomain();
		CodeSource cs = pd.getCodeSource();
		scan(cs.getLocation());
	}

	public void scan(URL url) {
		scan(url, url);
	}

	public void scan(URL base, URL url) {

		List<URL> files = listFiles(url);
		for (URL file : files) {
			fireEvent(base, file);
		}

		List<URL> dirs = listDirectories(url);
		for (URL dir : dirs) {
			scan(base, dir);
		}

	}

	private void fireEvent(URL base, URL file) {
		for (ScannerListener listener : listeners) {
			listener.resourceFound(base, file);
		}
	}

	public List<URL> listDirectories(URL directory) {
		for (ScannerPlugin plugin : plugins) {
			List<URL> ret = plugin.listDirectories(directory);
			if (ret != null) {
				return ret;
			}
		}

		throw new RuntimeException("ScannerPlugin not found: " + directory);
	}

	public List<URL> listFiles(URL directory) {
		for (ScannerPlugin plugin : plugins) {
			List<URL> ret = plugin.listFiles(directory);
			if (ret != null) {
				return ret;
			}
		}

		throw new RuntimeException("ScannerPlugin not found: " + directory);
	}

}